Preparation of Fumed Silica/polydimethylsiloxane Superhydrophobic Coating on Tooth Enamel Surface and Evaluation of Its Cytotoxicity and Antibacterial Ability

doi:10.13701/j.cnki.kqyxyj.2022.08.006

Abstract

Abstract: Objective: To prepare fumed silica/polydimethylsiloxane (SiO₂/PDMS) superhydrophobic coating on the surface of tooth enamel, and evaluate the cytotoxicity and antibacterial ability of the superhydrophobic coating. Methods: Different mass percentages of hydrophilic and hydrophobic SiO₂ and PDMS were dissolved in n-hexane and other related additives to form suspension solution and sprayed on enamel surface to form superhydrophobic coating. The contact angle and sliding angle of coating were measured by contact angle measuring instrument. Scanning electron microscopy (SEM) was used to observe the microstructure. X-ray photoelectron spectroscopy (XPS) was used to analyze its element concentration. Fourier transform infrared absorption spectrometer (FTIR) was used to analyze the inner group of the coating. Cytotoxicity test was performed to detect its biocompatibility. Automatic colony forming unit (CFU) was used to verify its anti- streptococcus mutans adhesion ability. Results: The best hydrophobic effect was when the hydrophilic fumed silica: hydrophobic fumed silica was 1∶1. At this moment, the average contact angle reached 164°, and the sliding angle reached 1.4°. The superhydrophobic effect comes from the surface roughness provided by nano-SiO₂ particles and the low surface energy provided by PDMS. MTT results showed that the coating had good biocompatibility. Antibacterial test showed that the antibacterial effect of superhydrophobic coating was better than that of control group. The anti-adhesion effect was stable within 6 h, reaching more than 87%. Conclusion: A biocompatibility superhydrophobic coating was successfully constructed on the enamel surface. The coating has good adhesion resistance to Streptococcus mutans, which provides ideas for the development of oral caries prevention sprays.

Key words: superhydrophobic, antibacterial, anti adhesion, Streptococcusmutans, PDMS

WU Yihao, ZHU Li, ZHOU Xin, LUO Yixuan, HUANG Shengbin, LIN Jixing, MA Jianfeng. Preparation of Fumed Silica/polydimethylsiloxane Superhydrophobic Coating on Tooth Enamel Surface and Evaluation of Its Cytotoxicity and Antibacterial Ability[J]. Journal of Oral Science Research, 2022, 38(8): 725-730.

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